No announcement yet.

SLAYER 450 CFM VS tunnel ram pair on Offy dual-quad intake?

  • Filter
  • Time
  • Show
Clear All
new posts

  • SLAYER 450 CFM VS tunnel ram pair on Offy dual-quad intake?

    Hope this is the right place - "installation" etc.
    I have a car with an Offy dual-quad intake. The intake currently has a pair of Edelbrock 1406 carbs which are a good ten years old, worn, and I'm not a fan, to be blunt.
    I also believe the 1200 or so CFM is a bit much for my engine (a bored AMC 360, about 37? cubes now, with 280H cam, headers).
    I was looking for something of newer design, a bit less total CFM and better than what's on the car now.
    My question is related to spacing and mounting on the Offy dual-quad intake.
    The Edelbrocks sit with the air filter studs at 8" apart. So front mounting stud of the rear carb to the front mounting stud of the front carb is 8"
    The distance (center to center) of the front mounting studs of the rear carb to the rear mounting studs of the front carb is 2.375"
    This is with the adapters on the intake for the Edelbrock bolt pattern and spacing. I haven't measured the pattern so can't say how it compares to the QF Slayer tunnel ram pair I am looking at on this page:

    Bottom line, with that pair fit my intake without tricks such as mounting them sideways or mounting one forward and the other backward facing and so on?
    Will they fit, both facing forward, on my intake with that spacing, and do I need different carburetor adapters for the intake or will these bolt right on where the Edelbrocks are now?

    Car is a '73 Javelin, AMC 360 bored, 280H Comp cam, Hooker coated headers, also requires linkage for throttle valve since it's a MOPAR 272 transmission.
    I made the throttle linkage myself so can likely fabricate what's needed there IF these would fit. Thanks.

  • #2
    That's some funky throttle linkage. You might want to rethink the throttle cable from the pedal's mounting angle.
    Anyway, if you mount the Holleys sideways, you most likely can't get to the idle screws, without using a custom built screwdriver. Basically a ratcheting one, that's been ground down, and the bit welded to it.
    On behalf of every manufacturer, delivery drivers, supply chain representatives, and workers of the world, "We're Sorry."


    • #3
      The throttle actually works quite well and is 150% better than the prior owner had it, where you had to stand on the pedal to get it to start to move then the cable went over center and you suddenly found it floored. He had used machine screws to "bolt" a flat piece of aluminum to connect the two throttle levers and the throttle cable had to pull UP as well as back. No concern here, especially as I want to be rid of these carbs anyway.
      But at this time, the throttle is smooth operating, I can get both open fully (it's one to one now) and the transmission throttle valve linkage works perfectly to control shifting. Besides, there's pretty much no clearance between the bracket you see and the firewall where the throttle cable exits - bee around on that for months. Based on cable, where it exits through firewall, distance from firewall to carburetors, and so on, at this time it's as good as possible, but like I say - if I have my way, these will be gone so the point will be moot.

      I don't want to mount carburetors sideways, maybe I wasn't clear in my message.
      I want to know of the slayer pair can be mounted forward, as normal, and will they clear each other.
      I never intended to imply I want to mount carburetors sideways, sorry if it looked as if I did. In fact, I will not mount any carburetors sideways on my car (or this intake, it wouldn't work well that way!)

      If the Slayers won't work forward, then I simply will not buy them. That's why I want to know if they will mount in this intake using the dimensions I supplied.
      The car runs and puts out nearly over 376 HP at the flywheel, but I hate these carbs and think the thing can do better with better technology and smaller carbs.


      • #4
        If you get the Offenhauser manual, or their catalog, they'll have a list of carburetors that they recommend for that intake. They generally recommend one particular Holley carb, but I don't know what the part number is.
        On behalf of every manufacturer, delivery drivers, supply chain representatives, and workers of the world, "We're Sorry."


        • #5
          Offy catalog doesn't show this intake. It's 10 years old and they show only the high-rise version.
          I've looked at their extremely limited PDF files (catalogs) off & on for a year and there's nothing in there.
          I guess no one knows any facts as far as will THESE QF carbs, will this pair fit. Perhaps no one has tried or has one of these low-rise 360s from yeas ago.


          • #6
            According to Offenhauser, you need a pair of 651 to 694 CFM carburetors, for your size engine, and a 280H camshaft used.
            On behalf of every manufacturer, delivery drivers, supply chain representatives, and workers of the world, "We're Sorry."


            • #7
              Last year, I inquired about the Tunnel Ram pair. l think from memory you'll need 9 1/8th to 9 1/4 inch between the front studs of each carb to fit them.
              Click image for larger version

Name:	IMG_1326.jpg
Views:	1
Size:	98.4 KB
ID:	343471
              The smaller cfm carbs will make the engine more responsive,especially if it is street driven and initially setup properly
              Last edited by Panoz78; 06-25-2019, 06:27 AM.